Exercise reverses decline in cell function

The health benefits of exercise are many and varied (and proven), but that doesn’t mean that we always understand exactly how or why this is so.

Some light, however, has been shed on the way in which exercise promotes the rebuilding of structures with cells that degrade as we age.

Researchers divided 72 participants (half of whom were female and half male) into two groups: the ‘young’ group’s subjects were aged 18 to 30 years, and the ‘older’ group’s subjects were aged between 65 and 80 years.

Both groups were then sub-divided again, into three exercise groups, one of which undertook high intensity interval biking; another of which did strength training; and the third of which participated in a combination of both.

Biopsies were taken from thigh muscles prior to and following the exercise program to analyse any change in muscle cells. While strength training was shown to increase muscle mass, the HIIT exercisers proved to have reaped the greatest benefits in terms of mitochondrial function.

While the younger group experienced a 49 per cent increase in mitochondrial capacity, the older group enjoyed even greater gains of 69 per cent.

Mitochondria play a key role in transporting chemical energy within cells, but their ability to do so declines as we age. The study results showed that exercise essentially reversed this decline.

Commenting on the findings, the study's senior author, Dr Sreekumaran Nair, said: ‘Based on everything we know, there's no substitute for these exercise programs when it comes to delaying the ageing process. These things we are seeing cannot be done by any medicine.’